Hemispherically-shaped pessaries designed to cover the cervix are generally known in the prior art. Such pessaries are used for various purposes, but most typically are employed as a vaginal contraceptive to prevent pregnancy. A particularly preferred cervix-covering pessary comprises a vaginal contraceptive of the type generally disclosed in U.S. Pat. No. 4,198,976 issued to Drobish et al. on Apr. 22, 1980, said patent being hereby incorporated herein by reference. The cervix-covering, vaginal contraceptive disclosed in the aforementioned patent to Drobish et al. is generally hemispherically shaped, and delivers spermicidal surfactant. The concave portion of the contraceptive unit is designed to cover the cervix in-use. Accordingly, proper installation of the unit in the vaginal cavity is of critical importance.
Pessary insertion devices of various types are also known in the prior art. U.S. Pat. No. 2,540,325 issued to De Bray et al. on Feb. 6, 1951 discloses a pessary and an inserter which may be threadedly engaged therewith. After the pessary has been inserted into position, the handle must be unthreaded from the lower end of a shaft which is secured to a cover in the pessary.
U.S. Pat. No. 2,818,856 issued to Kohl on Jan. 7, 1958 discloses a cervical cap applicator which is mechanically actuated. The cap is deformed as generally shown in FIG. 4 by advancing sleeve 26 along arms 22, 24 to permit insertion within the vaginal canal. Upon final seating of the cervical cap, the indicator rod 30 is advanced lengthwise in tubular handle 16, and the resulting outward displacement of the indicator or gauge knob 30a from the handle's end flange 16a indicates the fact of completion of the installation.
U.S. Pat. No. 2,830,582 issued to Ljung on Apr. 15, 1958 discloses yet another pessary introducer. However, the pessary is disengaged from the introducer by disengaging the lower edge of bead 18 from the recess 2 on the introducer by means of the forefinger of the user's free hand. Accordingly, the user's hand must be inserted into the vaginal cavity during the pessary insertion process.
French Pat. No. 1,271,008 issued to Seyberlich on Jan. 12, 1962 discloses an inserter for a cervix-fitting device comprising a squeeze bulb 9 connected to a suction cup 8 by means of a passageway 10. As shown in FIG. 5, the suction cup is caused to adhere to the surface 1 of the member to be inserted into the cervix opening by means of vacuum created by momentary deformation of bulb 9. Since the volume of the squeeze bulb 9 is large in relation to the size of the suction cup 8, it would appear that further squeezing of the bulb after insertion of the cervix-fitting device vitiates the vacuum, thereby discharging the device inserted into the cervix opening from the suction cup 8.
Such prior art vaginal product insertion devices are, however, deficient in one or more respects. Namely, they are difficult for the operator to use without significant training, they are complex to manufacture, they are high in cost due to the presence of numerous moving parts, and, at least in some instances, they require insertion of the user's hand into the body cavity to discharge the pessary from the inserter. Furthermore, the degree of control which the operator can exert over the pessary is quite limited after insertion of the unit into the body cavity, thereby making reliable placement over the cervix difficult for the untrained operator.
Accordingly, it is an object of the present invention to provide an apparatus for safely and reliably installing a generally hemispherically shaped pessary over the cervix, which apparatus minimizes the chance of injury to the operator or damage to the pessary during the insertion process.
It is another object of the present invention to provide such an insertion apparatus which permits the operator to control both the speed of ejection and the pressure applied to the pessary during the discharge process.
Another object of the present invention is to provide improved gripping of the pessary during insertion to minimize the chance of prematurely discharging the unit into the vaginal canal prior to alignment with the cervix.
Another object of the present invention is to ensure that the concave surface of the pessary covers the cervix by providing suitable orientation indicia on that portion of the insertion apparatus which is external to the user's body during the insertion process.
Another object of the present invention to provide a pessary inserter wherein the operator, whether the wearer or a third party administering treatment to the wearer, need only touch the handle of the inserter to complete the insertion process once the pessary has been installed thereon.
It is still a further object of the present invention to provide an insertion apparatus which can be easily manufactured at low cost, thereby facilitating either partial or complete disposal after a single use.